$sudo cp ~/Downloads/terraform /usr/local/bin
$terraform -version
Terraform v0.12.2

aws configure

# the ec2 vm even if it is ubuntu instead of amazon linux will have the aws secret key provisioned if the AWS CLI was installed 

- verify
ubuntu@ip-172-31-94-184:~$ ls ~/.aws
config  credentials
ubuntu@ip-172-31-94-184:~$ cat ~/.aws/credentials 
[default]
aws_access_key_id = A**
aws_secret_access_key = Dl****l

# get the latest
wget https://releases.hashicorp.com/terraform/0.12.7/terraform_0.12.7_linux_amd64.zip
$ sudo apt install unzip
$ sudo unzip terraform_0.12.7_linux_amd64.zip terraform
Archive:  terraform_0.12.7_linux_amd64.zip
  inflating: terraform               
$ sudo cp terraform /usr/local/bin
$ sudo chmod 777 /usr/local/bin/terraform 
$ exit

# upload a minimal template
obrienbiometrics:terraform michaelobrien$ scp aws_instance.tf ubuntu@bastion.obrienlabs.cloud:~/
aws_instance.tf                                                   100%  102     1.1KB/s   00:00
# go back into the box    
obrienbiometrics:terraform michaelobrien$ ssh ubuntu@bastion.obrienlabs.cloud

$ terraform init
* provider.aws: version = "~> 2.17"
Terraform has been successfully initialized!

$ terraform apply

sudo cp ~/Downloads/terraform /usr/local/bin/
sudo chmod +x /usr/local/bin/terraform
terraform init
* provider.aws: version = "~> 2.12"
Terraform has been successfully initialized!

# leave out your creds for auto discovery except the region
obrienbiometrics:terraform michaelobrien$ cat aws_instance.tf 
resource "aws_instance" "example" {
  ami           = "ami-2757f631"
  instance_type = "t2.micro"
}
provider aws {
  region = "us-east-1"

}

obrienbiometrics:terraform michaelobrien$ terraform apply
provider.aws.region
  The region where AWS operations will take place.
Do you want to perform these actions?
  Enter a value: yes
aws_instance.example: Creation complete after 35s [id=i-0c85247989abb315a]
Apply complete! Resources: 1 added, 0 changed, 0 destroyed.

# see terraform.tfstate
# modify ami
terraform apply
Apply complete! Resources: 1 added, 0 changed, 1 destroyed.
# destroy
terraform destroy
Plan: 0 to add, 0 to change, 1 to destroy.

$ terraform init
Initializing the backend...
Initializing provider plugins...
- Checking for available provider plugins...
- Downloading plugin for provider "aws" (terraform-providers/aws) 2.26.0...
The following providers do not have any version constraints in configuration,
so the latest version was installed.
To prevent automatic upgrades to new major versions that may contain breaking
changes, it is recommended to add version = "..." constraints to the
corresponding provider blocks in configuration, with the constraint strings
suggested below.

* provider.aws: version = "~> 2.26"

Terraform has been successfully initialized!
You may now begin working with Terraform. Try running "terraform plan" to see
any changes that are required for your infrastructure. All Terraform commands
should now work.
If you ever set or change modules or backend configuration for Terraform,
rerun this command to reinitialize your working directory. If you forget, other
commands will detect it and remind you to do so if necessary.

# if you don't have the AWS CLI installed yet - create the aws credentials file and validate it
https://docs.aws.amazon.com/cli/latest/userguide/cli-configure-files.html
$ vi ~/.aws/credentials
[default]
aws_access_key_id=AKIAIOSFODNN7EXAMPLE
aws_secret_access_key=wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY

$ terraform plan
Refreshing Terraform state in-memory prior to plan...
  # aws_instance.example will be created
  + resource "aws_instance" "example" {
      + ami                          = "ami-2757f631"
Plan: 1 to add, 0 to change, 0 to destroy.

$ terraform apply

Instance:  i-0bf09a07a574e5c53Public DNS: ec2-52-91-61-19.compute-1.amazonaws.com

ubuntu@ip-172-31-94-184:~$ terraform -version
Terraform v0.12.6
+ provider.aws v2.17.0

Your version of Terraform is out of date! The latest version
is 0.12.19. You can update by downloading from www.terraform.io/downloads.html

terraform init